Driving device for sewing-machines.



H. CORRALL.

DRIVING DEVICE FOR SEWING MACHINES.

APPHCATION FILED OCT. I9. 1912.

1 ,1 92,827. Patented July 25, 1916.

2 SHEETS-SHEET l.

E E 5 4 i i W/T/VESSES: INVENTOI? J/QM M ATTORNEY H. CORRALL.

DRIVING DEVICE FOR SEWING MACHINES.

APPLICATION mzo OCT. 19. m2.

1 1 92,827. I Patented July 25, 1916.

2 SHEETS-SHEET 2.

W/TNESSES: 7 63 Mum/r01? l a. o

HERBERT CORRALL, 0E PARIWIEW, HEE NsEURGH, SCOTLAND, ASSIGNOR TO THESINGER MANUFACTURINGCOMPANY, A CORPORATION on NEW JERSEY.

DRIVINGDEVICE FOR SEWING-MACHINES. 7

Specification of Letters Patent.

Patented July 25, 1916.

Application filed October 19, 1912. Serial No. 726,757.

To all whom it may concern: Be it known that I, HE BERT CORRALL, asubject of the King of the United Kingdom of Great Britain and Ireland,residing at Parkview, Helensburgh, Dumbartonshire, Scotland, haveinvented certain new and useful Improvements in Driving Devices forSewing-Machines, of which the following is a specification, referencebeing had therein to the accompanying drawings.

This invention relates to driving gear for power driven sewing machines,such as corset-cording machines, which are arranged in gangs or rowsupon a bench and driven by belts and pulleys from the under side of thebench, and it comprises devices for shipping the driving belt fromastationary idler pulley mounted on a bush or extension of the frameconcentric with a continuously rotating shaft to a driving pulley fixedupon the latter, and trip gear for unshipping the belt to stop themachine when a knot or other obstruction presents itself in the lengthof the cord.

The under-driving gear comprises a rotating shaft carried in bearings ofa hanger depending from the bench and having a central belt-pulley andat each end a fast and a loose belt-pulley carrying a belt,normally onthe loose pulley and extending through the bench to a sewing machinethereon. The fast pulley and loose pulley are made each with a singleflange on the outside and the loose idler or stationary pulley is ofslightly larger diameter than the fast or driving pulley, its grooveinclining or leading toward the driver so that the initial tension onthe belt is sufficient to roll the belt sidewise on to the driver assoon as the counter-resistance of the belt-fork or shipper is removed.

The belt-fork is attached to a bell crank which also serves as abrake-lever, the long arm of the lever being adapted to be lifted toshift the belt ontothe fast pulley to start the machine and to be heldthere by a pivoted latch or trip lever engaging a lug or projectionaffording. a detent shoulder on the lever-arm. The trip-lever extendsupwardly from its pivot and terminates in an aperture through which thecord used for cording corsets passes on its way to the sewing mechanism.Should a knot or ex cessively thick section of cord enter this eye itsdrag tilts the trip-lever against the resistance of a light spring anddisengages the latch from the belt-shifter arm, which, fallmg bygravity, moves the belt-fork to transfer the driving belt from the fastto the loose pulley and apply the brake so that the sewlng machine isstopped.

When the sewing machine is out of action, the initial pull of thesewingmachine belt 1s entirely removed from the underdrlvlng shaft, theloose pulley being mounted on a bush so that undue wear upon the shaftis obviated.

In the drawings, Figure 1 is an end elevation of a power bench or tablehaving a driving device embodying the present improvement. Fig. 2 is aplan upon a larger scale, of the driving device. Fig. 3 is an end viewand Fig. 4 a side view of the shipper-lever. Fig. 5 is an edge view andFig. 6 a side View of the latchor trip-lever. Fig. 7 is a partialsectional elevation, upon a still larger scale, of a portion of thehanger and the fast and loose pulleys sustained thereby.

The power bench or table is shown constructed with the end frames orstandards 1 upon which is mounted for vertical adjustment thelongitudinal platform 2 upon which may be secured at intervals thetransverse table members 3 suitably spaced apart and each sustaining thesewing machine heads 4t with their main-shafts in substantial alinementand carrying the grooved belt-pulleys 5 at their adjacent ends.

Secured to the under side of the platform 2 by means of bolts 6 is thebracket 7 with depending spaced and alincd bearing bosses 8 inwhich aresecured the oppositely eX tending bushings 9 affording exterior journals10 for the hubs '11 of the loose pulleys 12 each formed at the edgeadjacent the boss 8 with the brake-flange 13 and provided adjacent theopposite edge with the conical belt-receiving portion or face 14:.

Journaled within the bushings 9 is the driving shaft 15 to which issecured adjacent the pulley-hubs 11 'by means of the set-screws 16 thehubs 17 of the fast-pulleys 18 provided with the belt-receiving portionor face 19 of substantially conical form or contracted in diameter fromthe edge adjacent the loose pulley 12 toward the opposite edge which isformed with the guard-flange 20., The operative faces of the fast andloose pulleys are substantially of the same size at their adjacent edgesand together form a continuous substantially conical surface inclinedoutwardly from the boss 8 relative to their axis of rotation. Drivingbelts 21 and 22, represented herein of circular cross-section, embracethe pulley 5 of each sewing machine and either of the pulleys l2 and 18for connection of the driving shaft 15 with the main-shafts of thesewing mech anisms, the belt 22 being crossed so as to turn itsrespective pulley 5 in a direction suitable for turning the sewingmachine driving shaft in the proper direction to compensate for thereversed position of the sewing machine head relatively to the othermachine.

The shaft 15 has fixed thereon intermediate the bosses 8 the groovedbelt-wheel 23 over which runs the twisted belt 241 encircling thegrooved belt-wheel 25 upon the power-shaft 26 sustained by suitablehangers 27 depending from cross members 1 of the standards 1 and drivenby any usual or suitable means, such as an electric motor.

The bracket 7 is provided with divergently and upwardly extending arms28 sustaining the fulcrum-pins 29 and 30. Upon each of the fulcrum-pins29 is ournaled at the unction of its arms the hub 31 of the angularshipper-lever constructed with a lateral actuating arm 32 and a shorterdepending shipper and brake-shoe carrying arm 33 whose extremity has afacing 34: of leather or other suitable material to afford a brake-shoeadapted to engage the outer face of the flange 13 of the loose pulley.The righthand shipper-lever is shown provided in its arm 33 with asocket in which is secured by means of the set-screw 35 the shank 36 ofthe shipper-fork 37, while the other shipper-lever has a lateralextension 33 similarly provided with a socket in which is secured theshank 36 of the other shipper-fork 37, so that both shipper-forks arearranged upon the same side of the shaft 15 while the body portions ofsuch levers are arranged upon opposite sides of such shaft, asrepresented more particularly in Fig. 2.

The arm 32 of each shipper-lever is provided with a lateral lug orprojection 38 affording a detent-shoulder adapted for engagement by thehooked extremity 39 of the depending arm 40 of a latch-lever having ahub 41 journaled upon one of the fulcrumpins 30 and having an upwardlyextending arm 12 flattened at its extremity and provided with atransverse cord-guiding aperture 13. Each latch-lever is normally drawninto operative engagement with the lug 38 by means of a spring 41 havingone end secured to an apertured ear 40 of the depending arm 40 and theother similarly connected with an apertured ear 32 of the shipper-leverarm 32.

To set the machine in operation, the shipper-lever arm 32 is manuallyraised, as represented at the right in Fig. 1, whereby the brake-shoe 34is disengaged from the brakeflange 13 and the belt 21 is shifted fromthe loose to the fast pulley, the parts being held in such position byengagement of the hooked extremity 39 of the latch-lever with the lug 38under the action of the spring 14. In this position of the latch-lever,the cord 0, led through the guide-aperture therein and a suitableguide-eye 45 of the corder 16 upon the sewing machine bed-plate to thematerial being stitched, is freely drawn by the action of thestitch-forming mechanism. Upon the approach of any abnormal enlargementin the cord such as might be produced by a kink or knot or animperfection therein, liable to impair the free passage of the cordthrough the aperture 13, the resist ance thus produced causes thelatch-lever to be shifted sufliciently to disengage the member 39 fromthe lug 38, thereby causing the arm 32 to automatically descend bygravity, as represented at the left in Fig. 1, whereby the connectingbelt 22 is shifted over upon the loose pulley and the brake-shoeforcibly thrust against the flange 13 to stop the machine for r moval ofthe enlargement of the cord preparatory to the continued operation ofthe sewing machine. When it is desired to start the machine the arm 32of the shipper-lever is manually lifted whereupon the spring 44; acts toinsure the reengagement of the latch-lever with the shipper-lever whereby the latter is retained in running position. It will be observed thatwhen the machine 1s running, with the driving belt upon the smaller ofthe pulleys fixed upon the driving shaft 15, the action of the shipperin throwing the belt upon the loose pulley is assisted by thecentrifugal action of the belt. tending to cause it to creep up theinclined face of such larger pulley; while the actuation of theshipper-lever in the opposite direction to throw the belt upon thesmaller driving pulley tends to roll the belt upon itself upon theconical face of the now stationary loose pulley and thereby aids theshipper in performing its function.

By the means just described, the pull of the driving belts upon theshaft 15 is produced only when the driven machines are actually inoperation, and at other times, when the belts are under slightly greatertension upon the larger normally stationary pulleys, their cross-strainupon the driving shaft is wholly removed therefrom and is sustained bythe stationary bushing 9 10 of each bearing boss 8.

It has been common heretofore to ship a continuously running belt from aloose pulley or idler to a fast pulley upon a shaft to be driven; butaccording to the present invention the connecting belt is stationarywhen the driven machine is not in operation,

and the wear of the parts consequent upon the lateral pull of the beltis wholly removed, not only from the shaft but from the loose pulleywhich it embraces, when the driven machine is at rest.

Having thus set forth the nature of the invention, what I claim hereinis 1. A driving device for sewing machines comprising a driving and anidler pulley mounted for independent rotation upon a common axis andhaving conical faces inclined in the same direction relative to saidaxis and of substantially equal diameter at their adjacent edges, a beltadapted to connect said pulleys with a machine to be driven, a shipperfor shifting the belt from one to the other of said pulleys, a levercarrying said shipper and constructed and adapted to assume and remainin one extreme position for holding the belt upon the idler pulley, anda latch-lever for detaining the shipper-lever in its other extremeposition and formed with anaperture to receive a cord leading to thestitching mechanism, said lever being adapted to be shifted byimperfections in the cord to release said shipper-lever for permittingthe belt to be automatically shifted upon the idler pulley.

2. A driving device for sewing machines comprising a continuouslyrunning driving pulley and an'adjacent normally stationary idler pulleymounted for independent rotation upon acommon axis and having conicalfaces inclined in the same direction relative to said axis and ofsubstantially equal diameter at their adjacent edges, a belt adapted toconnect said pulleys with a machine to be driven, a shipper for shiftingthe belt from one to the other of said pulleys, a self-acting leverprovided with a detent shoulder and carrying said shipper which itnormally maintains in position to hold the belt upon the idler pulley,and a pivotally mounted latch-lever having one arm adapted to engagesaid shoulder of the shipperlever when in position to hold the belt uponthe driving pulley and another arm provided with an aperture throughwhich passes a cord leading to the stitching mechanism and by abnormalvariations in thickness of which the latch-lever may be shifted fordisengagement from the shipper-lever to cause the automatic shifting ofthe belt upon the idler pulley.

3. A driving device for sewing machines comprising a driving and anidler pulley mounted for independent rotation upon a common axis andhaving conical faces in-.

clined in the same direction relative to said axis, the faces of saidpulleys being of substantially the same diameter at their adja' centedges and that of the driving pulley be. ing the smaller of the tworelative to the opposite edges, a belt adapted to connect said pulleyswith a machine to be driven, a ship per for shifting the belt from oneto the other of said pulleys, a self-acting lever provided with a detentshoulder and carrying said shipper which it normally maintains inposition to hold the belt upon the idler pulley, and a pivotally mountedlatch-lever having one arm adapted to engage said shoulder of theshipper-lever when in position to hold the belt upon the driving pulleyand another arm provided with an aperture through which passes a cordleading to the stitching mechanism and by abnormal variations inthickness of which the latch-lever may be shifted for disengagement fromthe shipper-lever to cause. the automatic shifting of the belt upon theidler pulley.

4. A driving device for sewing machines comprising a continuouslyrunning driving pulley and an adjacent normally stationary idler pulley,a driven pulley, a belt adapted to connect the driven pulley with thedriving and idler pulleys, a shipper-lever adapted to automaticallyshift the belt from one to the other of said pulleys, a latch-leverdirectly engaging the shipper lever to hold the same in position todetain the belt upon one of said pulleys and adapted to engage a cordleading to the stitching-mechanism so that imperfections in the cordwill impart a releasing movement to the said latch-lever, and means forinsuring the reengagement of the latch-lever with the shipper-lever whenthe latter is manually actuated.

5. A driving device for sewing machines comprising a hanger having abearing boss, a driving shaft journaled in said hanger, a loose pulleyjournaled upon said bearing boss, a driving pulley fixed upon said shaftand having one edge of its face of substantially the same diameter asthe adjacent edge'of the loose pulley, a belt adapted to connect saidpulleys with a machine to be driven, a self-acting belt shipper adaptedto hold the belt normally upon the loose pulley, and a latch-lever fordetaining said shipper against movement into -normal position, saidlever being adapted to receive a cord leading to the stitching mechanismand to be tripped by imperfections in said cord.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing Witnesses.

HERBERT CORRALL.

Witnesses:

HENRY J. MILLER, HENRY A. KORNEMANN, Jr.

Copies of this patent may be obtained for five cents each, by addressingthe-Commissioner of Patents, Washington, D. G.

